Miniature antenna structures are known in this field. For example, a miniature antenna structure utilizing a geometry referred to as a space-filling curve is described in the co-owned International PCT Application WO 01/54225, entitled “Space-Filling Miniature Antennas,” which is hereby incorporated into the present application by reference. FIG. 1 shows one example of a space-filling curve 10. A space-filling curve 10 is formed from a line that includes at least ten segments, with each segment forming an angle with an adjacent segment. In addition, when used in an antenna, each segment in the space-filling curve 10 should be shorter than one-tenth of the free-space operating wavelength of the antenna.
It should be understood that a miniature antenna as used within this application refers to an antenna structure with physical dimensions that are small relative to the operational wavelength of the antenna. The actual physical dimensions of the miniature antenna will, therefore, vary depending upon the particular application. For instance, one exemplary application for a miniature antenna is a long wavelength HF communication antenna. Such antennas are often located onboard ships for which a small dimensioned antenna structure may be desirable. A typical long wavelength HF antenna onboard a ship that operates in the 2-30 MHz range may, for example, be ten (10) to fifty (50) meters in height, and can be significantly reduced in size using a miniature antenna structure, as described herein. In comparison, if a miniature antenna structure, as describe herein, is used as the antenna in a cellular telephone, then the overall physical dimensions of the miniature antenna will be significantly smaller.